Enantioselective Syntheses of C2-Symmetric Pyrazolones and Diones via One-Pot Organo-/Iodine Sequential Catalysis.

The catalytic diastereo- and enantioselective syntheses of C2-symmetric axially chiral 1,4-dicarbonyl derivatives with 2,3-quaternary stereocenters were achieved by utilizing an organo-/iodine binary catalytic strategy. The reactions proceeded well under mild conditions without metals or strong bases.

In situ generation of highly reactive allenes from nitrocyclopropanes: controllable synthesis of enynes and enesters.

A new and efficient strategy for ring-opening reactions of nitrocyclopropanes is developed for the first time for the divergent synthesis of enynes and enesters via in situ generated highly reactive electron-deficient intermediate allenes. Controllable approaches resulted in enynes and enesters with up to 89% and 90% yields, respectively. The reaction features easy operation, involves green solvents and simple inorganic bases, and is transition-metal free.

Merging catalyst-free synthesis and iodine catalysis: one-pot synthesis of dihydrofuropyrimidines and spirodihydrofuropyrimidine pyrazolones.

A new and efficient one-pot strategy combining catalyst-free synthesis and iodine catalysis has been developed for the synthesis of dihydrofuropyrimidines and spirodihydrofuropyrimidine pyrazolones. This approach affords products in moderate to high yields (up to 96%) with excellent diastereoselectivities (up to >25 : 1 dr). The reaction is simple to carry out and is metal-free.

Combining Organocatalysis and Iodine Catalysis: One-Pot Sequential Catalytic Synthesis of Chiral Spirodihydrobenzofuran Pyrazolones and Spirodihydrobenzofuran Oxindoles.

A new and efficient catalytic strategy that combines asymmetric organocatalysis and iodine catalysis was first developed for the one-pot Michael/iodization/SN2 nucleophilic substitution sequential catalytic synthesis of spirodihydrobenzofuran pyrazolones and spirodihydrobenzofuran oxindoles. The approach results in products with moderate to high yields (up to 93%), high to excellent enantioselectivities (up to 99% ee), and excellent diastereoselectivities (up to >99:1 dr). The reaction features simple operation and is metal-free and base-free.

Identification of rare paired box 3 variant in strabismus by whole exome sequencing.

AIM: To identify the potentially pathogenic gene variants that contributes to the etiology of strabismus. METHODS: A Chinese pedigree with strabismus was collected and the exomes of two affected individuals were sequenced using the next-generation sequencing technology. The resulting variants from exome sequencing were filtered by subsequent bioinformatics methods and the candidate mutation was verified as heterozygous in the affected proposita and her mother by sanger sequencing. RESULTS: Whole exome sequencing and filtering identified a nonsynonymous mutation c.434G-T transition in paired box 3 (PAX3) in the two affected individuals, which were predicted to be deleterious by more than 4 bioinformatics programs. This altered amino acid residue was located in the conserved PAX domain of PAX3. This gene encodes a member of the PAX family of transcription factors, which play critical roles during fetal development. Mutations in PAX3 were associated with Waardenburg syndrome with strabismus. CONCLUSION: Our results report that the c.434G-T mutation (p.R145L) in PAX3 may contribute to strabismus, expanding our understanding of the causally relevant genes for this disorder.

Corneal infection in Shandong peninsula of China: a 10-year retrospective study on 578 cases.

AIM: To determine the epidemiological characteristics, clinical signs, laboratory findings, and outcomes in patients with corneal infection in Shandong peninsula of China. METHODS: The medical records of 578 inpatients (578 eyes) with corneal infection were reviewed retrospectively for demographic characteristics, risk factors, seasonal variation, clinical signs, laboratory findings, and treatment strategy. Patient history, ocular examination findings using slit-lamp biomicroscopy, laboratory findings resulted from microbiological cultures, and treatment. RESULTS: Fungal keratitis constituted 58.48% of cases of infectious keratitis among the inpatients, followed by herpes simplex keratitis (20.76%), bacterial keratitis (19.03%) and acanthamoeba keratitis (1.73%). The most common risk factor was corneal trauma (71.80%). The direct microscopic examination (338 cases) using potassium hydroxide (KOH) wet mounts was positive in 296 cases (87.57%). Among the 298 fungal culture-positive cases, Fusarium species were the most common isolates (70.47%). A total of 517 cases (89.45%) received surgical intervention, including 255 (44.12%) cases of penetrating keratoplasty, 74 (12.80%) cases of lamellar keratoplasty which has become increasingly popular, and 77 cases (13.32%) of evisceration or enucleation. CONCLUSION: At present, infectious keratitis is a primary corneal disease causing blindness in China. With Fusarium species being the most commonly identified pathogens, fungal keratitis is the leading cause of severe infectious corneal ulcers in Shandong peninsula of China.

Epidemiological characteristics and risk factors of diabetic retinopathy in type 2 diabetes mellitus in Shandong Peninsula of China.

AIM: To determine the epidemiological characteristics and estimate the risk factors of diabetic retinopathy (DR) in patients with type 2 diabetes mellitus (T2DM) in Shandong Peninsula of China. METHODS: The cases of T2DM admitted to Affiliated Hospital of Medical College of Qingdao University, Shandong Province, China, from January 2006 to December 2010 were retrospectively reviewed. The epidemiological characteristics of DR were estimated. The cases were divided into two groups according to degrees of retinopathy: non-DR group and DR group. Logistic regression analysis was used to study the related risk factors of DR. RESULTS: The prevalence of DR in patients with T2DM was 25.08% (834/3326). There was significant difference between the average age for men (59.08±15.43 years) and for women (62.92±18.19 years, P=0.0021). The majority of DR occurred in women (female: male ratio=1.76:1, P<0.0001). The incidence rate of DR in urban (489/834) was higher than that in rural area (345/834, P<0.0001). In 834 DR patients, the mean duration of T2DM was 8.90±4.15 years (range: 0-16 years); 440 people (52.76%) had received varying degrees of health education about prevention and primary care of DM; and 473 people (56.71%) suffered from other DM complications confirmed at the same time. In addition, the incidence rate of monocular (551/3326) and binocular retinopathy (283/3326) were statistically different (P<0.0001). Factors associated (P<0.05) with the presence of DR included old age, lower health educational level, intraocular surgery history, longer duration of T2DM, accompanying with other DM complications, no standard treatment procedure, lower body mass index (BMI) and higher fasting plasma glucose (FPG), glycated hemoglobin A(1)C (HbA(1)C), urine albumin (UA), total cholesterol (TC), low-density-lipoprotein cholesterol (LDL-C). The risk factors (P<0.05) independently associated with the presence of DR were: longer duration of T2DM, lower health educational level, higher FPG, higher UA, lower BMI and higher TC. CONCLUSION: DR is highly prevalent in the patients with T2DM in Shandong Peninsula of China. Besides blood glucose, many factors are associated with the present and development of DR.

Effect of ginsenoside-Rg3 on the expression of VEGF and TNF-α in retina with diabetic rats.

AIM: To investigate the effect of ginsenoside-Rg3 on the expression of vascular endothelial growth factor (VEGF) and tumor necrosis factor-α (TNF-α) in retina with diabetic rats and its roles in preventing neovascularization in diabetes. METHODS: Sixty male Wistar rats were divided into 3 groups randomly: negative control group, diabetic control group and ginsenoside-Rg3 treatment group (5mg/kg, 0.2mg/mL) followed by establishing diabetic model. The expression of VEGF and TNF-α were measured after 8 weeks. RESULTS: There were significant differences among negative control group, diabetic control group and ginsenoside-Rg3 treatment group in the expression of VEGF and TNF-α (F=129.363, 211.992; all the P<0.01). VEGF and TNF-α expression were significantly higher in diabetic control group and ginsenoside-Rg3 treatment group than that in negative control group (P<0.01), with a significant reduction in ginsenoside-Rg3 treatment group than that in diabetic control group (P<0.01). CONCLUSION: Ginsenoside-Rg3 can down-regulate the expression of VEGF and TNF-α in retina, which may interfere in the development of diabetic retinopathy.

[Hydrogen peroxide induces expression and transcription of erythropoietin in the human retinal pigment epithelium cells].

OBJECTIVE: To investigate the expression of erythropoietin (EPO) in human fetal retinal pigment epithelium (hfRPE) cells exposed to oxidative stress induced by hydrogen peroxide (H(2)O(2)) and to study the mechanisms. METHODS: The hfRPE cells were isolated, cultured and identified. The content of malondialdehyde (MDA) and the activity of superoxide dismutase (SOD) of the hfRPE cells were examined. The changes of level of mRNA and protein of EPO in hfRPE cells exposed to oxidative stress were measured by semi-quantitative RT-PCR and immunocytochemical staining techniques. RESULTS: H(2)O(2) could increase the content of MDA and inhibit the activity of SOD in hfRPE cells. RT-PCR detected a significant increase of EPO mRNA level in cultured hfRPE cells exposed to oxidative stress. The level of EPO mRNA in the hfRPE cells reached a peak when exposed to 600 micromol/L H(2)O(2), then decreased after exposing to 800 micromol/L H(2)O(2). The immunocytochemical study detected that the changes of the level of EPO protein were similar to that of EPO mRNA. CONCLUSION: Oxidation stress by exposed to H(2)O(2) induces significant increase of EPO expression of hfRPE cells. Expression of EPO may be related to the survival and tolerance of hfRPE cells.

[Clinical and pathological analysis of choroidal metastatic carcinoma].

OBJECTIVE: To study the clinical and pathological characteristics of choroidal metastatic carcinoma. METHODS: The clinical data, pathological character, primary tumor origin and histological classification of 18 patients with choroidal metastatic carcinoma were analyzed retrospectively. RESULTS: Most patients had severe visual impairment. Solid mass was seen in the posterior pole of the eyes in all 18 patients through ocular fundus examination, 8 cases had retinal detachment. B scan and CT examination found flat or irregular masses. MRI examination had been performed on 5 patients, high signal intensities on T1W and low signal intensities on T2W were found. Five patients were adenocarcinoma, 4 were squamous carcinoma and 3 were undifferentiated carcinoma through pathological examination. Primary tumor was lung carcinoma in 10 cases (55%) and breast carcinoma in 4 cases (22%). CONCLUSIONS: Rapid decrease of visual acuity, flat neoplasm in ocular fundus and secondary retinal detachment are the main clinical characteristics of choroidal metastatic carcinoma. The most common primary tumor is lung carcinoma and the most common histopathological classification is adenocarcinoma. Imaging examination is helpful for the diagnosis of choroidal metastatic carcinoma.

[The mechanism of accumulative oxidative injury by hydrogen peroxide on human retinal pigment epithelial cells].

OBJECTIVE: To explore the effects of oxidative injury induced by hydrogen peroxide on human retinal pigment epithelial (RPE) cells. METHODS: Cultured human RPE cells were treated by 600 micromol/L hydrogen peroxide (H2O2) for 1, 6, 12, 24 and 72 hours. Cell viability was assessed by the MTT assay. Apoptosis was assessed by Annexin V-fluorescein isothiocyanate/Propidium iodium (Annexin V-FITC/PI) staining. The expression of clusterin was assessed by Western blot. RESULTS: (1) The treatment of RPE cells with 600 micromol/L H2O2 caused a time-dependent decrease of cellular viability. (2) Apoptosis was detected in cultured human RPE cells treated with 600 micromol/L H2O2 for 6 hours. The number of apoptotic cells reached a maximum at 24th hour after being exposed to 600 micromol/L H2O2 (P < 0.05). (3) Western blot showed the expression of clusterin protein was demonstrated in 6 hours exposure to 600 micromol/L H2O2, a significantly increasing of clusterin expression was observed overtime (P < 0.01). Thereafter the expression of clusterin protein decreased at 24th hour after being exposed to 600 micromol/L H2O2. At 72nd hour, the expression of clusterin protein was quite weak. CONCLUSION: Hydrogen peroxide can inhibits RPE proliferation and induces apoptosis and aging gene expression;the result suggest that accumulative oxidative injury induced by hydrogen peroxide in RPE in vitro may be similar to the aging changes in vivo.

[The protective effect of hypoxic preconditioning against light-induced photoreceptor degeneration in mice].

OBJECTIVE: To study the protective roles of hypoxic preconditioning in light induced retinal injury in a mice model and investigate the possible mechanism of related gene regulation. METHODS: 54 BALB/c mice were randomly divided into simple light exposure group (SL), hypoxic pretreatment group (HP) and control group (CON). The mice of SL and HP were continually exposed to light for 3 h, which built model of light-induced damage. Morphologic changes of photoreceptor cells in different group were examined by light microscope and the apoptosis was detected by TdT-mediated dUTP nick end labeling. Different expressions of c-fos and caspase-1 gene were examined by immunohistochemical staining. RESULTS: In group SL, the photic injury appeared very obviously and early. Different changes appeared in the outer nuclear layer after light exposure. Photic injury was aggravated following the increased light exposure. Positive staining of c-fos and caspase-1 could be seen in the outer nuclear layer. In group HP, the changes of retinal morphology appeared slightly and lately. Compared with group SL, caspsae-1 expression was decreased obviously, while no difference was seen in the expression of c-fos. The retinal structures was normal in the mice of control group and c-fos and caspase-1 were stained negative. CONCLUSION: Hypoxic preconditioning has neuroprotective effect on photoreceptor cells by inhibiting the expression of apoptosis-related genes in photic injured mice model. caspase-1 may be involved in the protective mechanism.

[Erythropoietin administration protects retina against light-induced retinal degeneration].

OBJECTIVE: To study whether recombinant human erythropoietin can pass through mice blood-retina barrier and the protective role in light-induced damage in retina. METHODS: After the injection of rHEPO, the content of rHEPO in 24 BALB/c mice retina was examined by enzyme linked immunosorbent assay (ELISA). 24 BALB/c mice were used to establish a light-induced damaged model, the difference of retina in rHEPO group and control group was compared using light microscope and TdT-mediated dUTP nick end labeling (TUNEL). RESULTS: The amount of retinal rHEPO in four deferent time points was (0.68 +/- 0.24) mU, (1.87 +/- 0.37) mU, (0.96 +/- 0.24) mU, (0.47 +/- 0.13) mU in 100 microg retinal total protein respectively by ELISA assay, there were statistical significances among groups. The density of rHEPO in the retina reached its peak at 4th hour after injection. Histology analysis: rHEPO group, at the 12th hour after light exposure the inner segment became condensed and disorganized. At the 36th hour the retina disorganized and vesiculated were seen in outer segments. At the 72nd hour the inner and outer segments were damaged more seriously and the outer nuclear layer became thinner and denser. On the 7th day, the retinal outer nuclear layer became thinner and condenses. rHEPO group showed a minimal damage in every time points but outer nuclear layer disorganized and vesiculated in inner and outer segments. No obvious changes in retinal thickness. The apoptotic cells were detected by TUNEL. At the 12th hour after light exposure, there were the apoptotic cells in outer nuclear layer near outer plexiform layer. At 36th hour the numbers of apoptotic cells were increased, however at the 72nd it was decreased obviously, only a few scattering apoptotic cells were revealed in the outer nuclear layer. Numbers of apoptotic cells between the rHEPO group and control group in outer nuclear layer were statistical significance (P < 0.01). CONCLUSIONS: rHEPO can pass through the mice blood-retina barrier and rHEPO has neuroprotective effect on mice retina. rHEPO may be used to treat degenerative retinal diseases.

Therapeutic effect of bFGF on retina ischemia-reperfusion injury.

BACKGROUND: Basic fibroblast growth factor (bFGF) plays important roles in retina degeneration, light injury, mechanical injury, especially in retina ischemia-reperfusion injury (RIRI). This study was to investigate the therapeutical effect of bFGF on RIRI and its mechanisms. METHODS: Experimental RIRI was induced by increasing intraocular pressure (IOP) in the eyes of 48 rats. These rats were divided into normal control, ischemia-reperfusion and bFGF-treated groups. Histological and ultrastructural changes of in the retina of different groups were observed, and the number of retinal ganglion cells (RGCs) was quantitatively analyzed under microscopy. Apoptotic cells were detected using the TdT-dUTP terminal nick-end labeling (TUNEL) method. The expression of caspase-3 was determined by streptavidin peroxidase (SP) immunohistochemistry. Atomic absorption spectrum method was used to evaluate the intracellular calcium changes. RESULTS: At the early stage of retinal ischemia-reperfusion injury, retina edema in the treated group was significantly eliminated compared with the untreated ischemic animals. RGCs in the bFGF-treated group was more than those in the untreated ischemic group during the post-reperfusion stages. In ischemic group, apoptotic cells could be found at 6th hour after reperfusion and reached the peak at 24 hours. At 72nd hour no apoptotic cells could be found.The changes in caspase-3 expression had a similar manner. The intracellular calcium of rat retina began to increase at 1st hour, reached the peak at 24 hours, and began to decrease at 72 hours. The change of the three markers in the treatment group showed a similar pattern, but they were all relatively less obvious. CONCLUSION: Apoptosis may play a vital role in RIRI. bFGF may has therapeutical effects on RIRI by inhibiting the increase of intracellular calcium and caspase-3 expression.

[Distribution and expression of basement membrane proteins in malignant eyelid tumors and its clinical significance].

OBJECTIVE: To study the distribution and expression of type IV collagen (Col IV), laminin (LN) and fibronectin (FN) in the basement membrane of malignant eyelid tumors so as to explore the relationships between the basement membrane and the degree of differentiation, metastasis and prognosis of malignant tumors. METHODS: Eighty-five paraffin-embedded specimens of malignant eyelid tumors including basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and sebaceous cell carcinoma were studied to identify the Col IV, LN and FN with immunohistochemical SABC techniques. RESULTS: A continuous intact basement membrane (BM) could be identified in all of the normal tissues and benign tumor specimens. In the malignant tumor specimens, the BM was defective or absent. The positive expression rate of Col IV in BCC, SCC and sebaceous cell carcinoma was 65% (24/40), 56% (16/25) and 40% (8/20). The positive expression rate of LN was 58% (23/40), 40% (10/25) and 35.% (7/20), respectively. The positive expression rate of FN was 33% (13/40), 36% (9/25) and 30% (6/20), respectively. The positive expression rate of these extracellular matrices was correlated with the degree of differentiation of the tumor. The difference of positive rate between highly-differentiated and poorly-differentiated tumors was significant (P < 0.05). In a short term follow-up (6-18 months), a statistically significant correlation (P < 0.05) could be observed between tumor recurrence and BM integrity. A higher recurrence rate and early recurrence were found in patients with interrupted BM. CONCLUSION: The absence of expression of Col IV, LN and FN was related to the invasive capacity and recurrence of the tumor. This result can be used as an index for clinical judgment of prognosis of the eyelid tumors.

[An experimental study of the therapeutical effect of bFGF in retinal ischemia/reperfusion injury].

OBJECTIVE: To investigate the therapeutical effect of basic fibroblast growth factor (bFGF) on retina ischemia/reperfusion injury. METHOD: Experimental retinal ischemia/reperfusion injury was induced by increasing intraocular pressure of rats eyes. 48 rats were divided into groups of control, ischemia/reperfusion and bFGF-treated, randomly. Apoptotic cells were detected using the TdT-dUTP terminal nick-end labeling at 1 hour, 6 hours, 12 hours, 24 hours, and 72 hours after reperfusion. The expression of caspase-3 at specified times was determined by Streptavidin Peroxidase immunohistochemistry. Atomic absorption spectrum method was used to evaluate the intracellular calcium changes of retinal tissues. RESULTS: In ischemia group, apoptotic cells began to appear at 6th hour after reperfusion and increased progressively with time. The number of apoptotic cells reached the peak 24 hour after reperfusion, and no apoptotic cells could be found at 72 hours. Changes in caspase-3 expression followed a similar trend. The intracellular calcium level of rat retina began to increase at 1 hour after reperfusion, and continued to increase with the reperfusion time. At 24 hours after reperfusion the intracellular calcium level reached the peak, and decline thereafter up to 72 hours. The patterns of change of the three markers of treatment group were similar to the above. However, the magnitude of changes was relatively lower. A statistically significant difference (P < 0.05) between the ischemia group and treatment group at 6th, 12th and 24th after reperfusion was observed. CONCLUSION: Apoptosis may play a vital role in ischemia-reperfusion injury of the retina. bFGF may have a therapeutical effect on ischemia-reperfusion injury by inhibiting the increase of retinal intracellular calcium stores and caspase-3 protein expression.